Operating mechanism for motor car clutches



Jan. 5, 1932.

R. G. COATES OPERATING MECHANISM FORMOTOR GAR CLUTCHES Original Filed "April 9,; 1928 7b (k255i:

75 (Jada/s J 2. (9.6mm

Patented Jan. 5, '1932 UNITED STATES-PATENT o IcE RAY G. OOATES, OF PASADENA, CALIFORNIA OPERATING MECHANISM FOR MOTOR CAR CLUTCHIS Original'application fil ed April 9, 1928, Serial No. 268,681. Dividedand this application'flled September 80,

1930. Serial no. 485,460, t

My invention relates to gas engine clutch operating mechanism for motor 'carsin which a spring is used to close the clutch" which is opened by pressure on a pedal which overcomes the stress of the spring. If the open condition of the clutch is more than momentary the effort required to keep the clutch spring stressed becomes tiring.

An object of my invention is to-render less laborious the efiort required to open the clutch. to v A second object is to make the effort of holding the clutch open so small that it may be held open indefinitely with ease.

A third object is to so arrange the mechanism that the clutch is either open or closed and thus reduce the wear due to too much slipping. 4 A fourth object is to obtain the above characteristics without interfering with theoperation of the clutch by the foot, in the usual manner, if desired. 1

Y I accomplish the above results by using auxiliary power to assist the driver, in his effort to open the-clutch, and to hold itopen; It is possible to carry out my invention in many ways. The design herewith shown .is-

- diagrammatic and illustrates one way of ap;

' plying my invention yet I contemplate ap v 30 plying it to any motor car clutch to which it may be applicable and do not limit myself to the particular construction illustrated.

This application results from a division declared in the case of my application for Letters Patent for operating mechanism for clutches filed April 9th, 1928, Serial Number 268,631, and the drawings in this application are parts of the drawings of the original application. I

In applying power to operate. motor car clutches it is usual to so arrange matters that the clutch opens in proportion to the stroke of the pedal. This requires the pedal to make a full stroke in order to fully open the clutch. This complete long stroke every time the clutch is openedcauses unnecessary work. Again it is undesirable to open the clutch simultaneously with shutting ofi'the fuel to the idlin point as this prevents 150 the engine from eing quickly used as a brake, In my improvement changes in-the vfuel supply do not affect the clutch opening mechanism, therefore the clutch will remain closed until it is intentionally o ened and the engine may be used as a bra e without special provision. I

In thedrawings a clutch controlling member, here shown as a lever, 8, is carried by a fulcrum, 9, so that movements of the lever 8 in one direction will cause the clutch to open while movements of the lever in the opposite with the lever 8. Both of these forms of con nection are now common in thisart' so no further illustration of this connection is deemed necessary. 7

7 Attached to the lever 8, b the pin 28, is a connecting rod 15. The ot er end of 15 is pinned, by the' pin 35, to the piston 14 which closes the otherwise open end of the cylinder 13, which latter is suitably secured to the chassis. The piston14 moves in the cylinder 13 and normally is positioned as shown in Figure 1. The cylinder 13 is connected by the conduit 38 to the part 17 of the valve body 19. This latter also carries a port, 16, leading by the conduit 34 to the conventionally indicated intake manifold '31 with its conventional throttle valve 32. A valve, 18, covers the port 16 and at no time is this valve to connect port 16 to the atmosphere. A pedal lever, 10, carrying a pedal,11, at one end is jou'rnaled at its other'end on the fulcrum 9. A stop, 12, is fixed to the chassis so as to limit the movement towards the right of the pedal 10. The spring, 29, is/c'onnected to the chassisso that its reactiop will insure the return of the lever 10 to the stop 12 when pressure is removed from the pedal 11. This is the normal position of the lever 10;

, Connected to the lever 10 between the fulcrum 9 and the pedal 11, by the pin 36 is a. connecting rod 20. The other end of 20 is connected to the valve 18 by the pin37. When the pedallever moves to the left the valve 18 will also move to the left and will ultimately connect ports 16 and 17 and thus open -manifold 31. The pedal lever 10 is to be so placed that when the valve 18 has connected the cylinder 13 to the intake manifold 31 the lever 10 comes in contact with the lever 8.

. In order to make this contact of the lever 10 rsjusting the screw 22 the with the lever 8 at the moment the valve 18 has reached the full open phase the screw 22 may be used as a contact point. Byadlever 10 may be brought'in contact with lever 8 just as the valve 18 becomes fully opened. In this conditi'on, the engine being assumed to be running, the piston 14 will move to the left and, through the connecting rod 15, will carry the lever 8 with it, thereby opening the clutch.

.In order to fully open the clutch it is not necessary for the pedal to move any farther to the left than enough to open the valve 18.

This is a quite small fraction of the totalstroke of the usual clutch pedal to accomplish this same result. Further the work of stressing spring 29 is very much less than that of overcoming the stress on the clutch v spring.

.If the engine is not running the pedal 10 maybe pressed still farther to the left and thus make a contact wit-h the lever 8 and push v it-before it and thus open the clutch. In

this case the valve 18 will move farther to the left than in the normal valve stroke, which the pedal is the reason forthe extra length of the valve body and valve previously mentioned.

The valve 18 opens by pressure on the pedal 11 and closes by the release of this pressure. The opening movement of the clutch controlling member has no effect to close the valve at any stage of the valve stroke, therefore when the valve has opened the piston will make a.

full stroke provided the pedal lever has not moved in the meantime. Thus the clutch moves to 'either the open or closed phases without undesired slipping between the faces of the clutch. To prevent the clutch from grabbing, when the clutch is closed, the valve 18 may permit only a small openingto the port 17. when the pedal 11 is released, thus allowing the atmospheric pressure to enter the cylinder as slowly as may be necessary to .make a smooth'start. This is shown at the left, hand:end of valve 18 .where the port 17 is still largely covered bythe valve although lever 10 is in released position against the sto 12. This does not affect the full opening 0 the port 17 when pressure is -11 the lever 10 returns to the stop 12 through the reaction of the spring 29. This moves the valve 18 back so as to cover only the port 16 and port 17 is open to the atmosphere through the end 'of the valve chamber 19; The clutchspring then moves the lever 8 back to its normal position, which act simultaneously carries the connection 15 and piston 14 with it and the parts are then in the normal position of clutch closed. It will be seen that the clutch may be held open indefinitely against the heavy resistance of the clutch spring since the only resistance to be overcome is the small resistance of the spring 29.

I claim:

The combination with an intake manifold of a motor car motor, a throttle, and a clutch controlling member of a spring closed clutch, of a piston, a means for operatively connecting said piston to said clutch controlling member, a cylinder in which said piston is IIIIIOVHblB having a closed end in advance of t e said intake manifold to the closed end of said cylinder, a pedal lever adapted to move said clutch cont-rolling member after a normal short stroke without moving said member during said-normal short stroke, a yielding means, not actuated by fluid pressure, adapted to maintain said pedal lever in released position, a valve in said suction conduit connected, by an inelastic operable connection, to and controlled solely by said pedal lever and adapted to admit atmospheric pressure to said cylinder and to cut off communication with said intake manifold when said pedal lever is released and to cut off atmospheric pressure from said cylinder. and open communication with said intake manifold to permit a full stroke to said piston when said pedal lever is stressed and moved. to the extent of said normal short stroke, the communication of said cylinder with the atmosphere and with the said intake manifold being unchanged by movements of said pedal lever beyond the limits of said normal short stroke or by movements of said piston or by variations in the pressure in said cylinder.

RAY G. COATES.

iston, a suction conduit leading from 

